Flanged carbon steel pipe for industrial exhaust ducts

[TxKnight93]

What are advantages and disadvantages of using a rated & flanged carbon steel for industrial air exhaust ducts?

 

[moltenmetal]

Cost...a typical duct uses a tiny fraction of the metal that welded pipe does, is galvanized so there is no exterior finishing needed, and is joined by methods which take a tiny fraction of the labour required to do butt welded joints in pipe.

 

[JStephen]

Weight might be another consideration, if you're hanging it off of roof structures.

 

[RossABQ]

What is the exhaust stream, something extremely corrosive? Or is it high vacuum/pressure? Why would you even consider pipe for this?

 

[TxKnight93]

Ducting is to exhaust air with moisture from a dryer to exhaust blower, and now having to decide what standards to use between ASME Section VIII if these ducts can be similar to atmospheric tanks w/o top & bottoms, or ASME B31.3 if these ducts can be a pipe, or trust my gut feeling that these ducts should be designed and fabricated per SMACNA.